"So there's going to be a strong reaction in both directions for this mystery Houseguest."Ahead of season 27, here are the 12 best Big Brother seasons to watch, all of which are available to stream on Paramount+.

Grab a life vest, floaters, because look who just resurfaced back in the Big Brother house.

Big Brother 27,' hosted by Julie Chen Moonves, premieres on Thursday,. See which houseguests are in power as HoH, who is nominated and who has been evicted so far

Here's everything to know about the rules all Big Brother contestants must follow. One of the most crucial elements in Big Brother is eliminating the noise from the outside world so contestants can fully focus on the show. Houseguests do not have access to the internet or any other form of outside communication.

"Big Brother" revealed its mystery houseguest for season 27 Thursday: the legendary Rachel Reilly. Reilly entered the house to meet the other 16 houseguests during the end of the premiere episode July 10, as she ultimately told them she was staying and competing with them this summer.

Big Brother 27 - The stage is set. The lights are dim. Hotel Mystère has welcomed its first batch of guests but do not let the chandeliers and velvet drapes fool you. Behind every door hides something darker.

The cast of "Big Brother" Season 27 has been revealed — with one "Mystery Player" set to make a surprise entrance.